Measures to Reduce Hydrogen Content in Weld Metal
Welding is a widely used method of joining materials. In addition to the cause of incorrect welding parameters or environmental problems, hydrogen is an important factor that affects the quality of welded joints. There are many sources of hydrogen in welding activities. The welding materials, welding environment, and even the surrounding environment are all sources of hydrogen. Therefore, it is important to reduce the amount of hydrogen in the weld metal. The following methods can be used to reduce hydrogen content in weld metal:
1.The selection of welding materials: The choice of different welding materials can affect the hydrogen content in the weld metal. Generally, the hydrogen content of welding rod is lower than that of carbon steel, and the higher the voltage, the less hydrogen content of weld metal. Therefore, it is suitable to select the welding materials with lower hydrogen content, such as the low-hydrogen electrode, MINI-ARC tungsten inert gas (TIG) welding rod and flux-cored welding wire, to reduce hydrogen content in the weld metal.
2.Using correct welding parameters: When using welding machines, the correct welding parameters should be selected. The low-hydrogen electrode and TIG welding materials should be used properly to reduce the input of hydrogen. The welding current of the low-hydrogen electrode and the arc voltage of TIG welding should be increased to reduce the amount of hydrogen in the weld metal.
3.Controlling welding environment: The welding environment should be suitable for reducing the content of hydrogen in the weld metal. In addition, the wind speed of the welding environment should not be too strong, otherwise the hydrogen in the air will easily enter the weld pool. Proper wetting of the weld area with water is also helpful in reducing hydrogen.
4.Improving the inspection process: Welding inspection is very important for controlling the hydrogen content in weld metal. In particular, it is necessary to ensure that the weld pool temperature is not too high, and the pressure of the welding gas should be kept in the appropriate range. In addition, the amount of welding rod and TIG welding rod should be well controlled.
These are the four methods for reducing hydrogen content in weld metal. It is important to follow these methods to ensure that the welded joint is of good quality and without the risk of hydrogen-induced cracking. In addition, it is also necessary to pay attention to the prevention of other problems during welding activities, such as the production of under-filled or incomplete welds.
